Carburetor process for acetylene reactions



June 7, 1949.. a. SELLER ETAL 2,472,084

I CARBURETOR PROCESS FOR ACETYLENE REACTIONS Filed Oct. 10, 1945 4Sheets-Sheet 1 /0 PRESSURE :E i REGULATOR i5 ACETYLENE HOLDER CONDENSER2 SURGE TANK 6 AUTOCLAVE v f 3 COMPRESSOR 6 CARBURETOR PREHEATER DILUENTPUMP INVENTORS H. BELLE P. R. CHRIST BY F. WUERTH ATTORNEYS 3mm TI,1949. H. BELLER ETAL 2,472,034

CARBURE'POR PROCESS FOR ACETYLENE REACTIONS Filed Oct. 10, 19 5 4Sheets-Sheet 2 ACETYLENE HOLDER CONDENSER s-rmppmc;

STILL E: DEGA' i" 40 t PRODUCT if 37/ E: RECEIVER 3: r

1 REACTION PUMP LUE TOWER 5 9 az l 4 I: 1?

MAKE UP STILL BOTTOM MAKE UP TANK CAR PUMF; 47

lNVENTORS s N O I T C A E R m E A L Y UT E C RA E R m as s B E w H R P R0 T E R U B R A 0 June 7, 1949.

4 Sheets-Sheet 3 Filed Oct. 10, 1945 III/l7 INVENTORS ATTORNEYS June1949- I H. BELLER ETAL 2,472,,G84

CARBURETOR PROCESS FOR ACETYLENE REACTIONS Filed Oct. 10, 1945 4Sheets-Sheet 4 i GAS TO FIE-ACTION DILUE NT I CARBURETING b 7,314

TOWER HEATER HEATED BY FIWUERTH b y y i ATTORNEYS Patented 7 caammn'roaraocass ron' amc'nons Acumen Hans Beller, Craniord, and Robert E. Christand Fritz Wuerth, Elizabeth, N. L, assignors to General Aniline & FilmCorporation, New York, N. Y., a corporation of Delaware t A ApplicationOctober 10, reasons: No. cameo The present invention an improved methodof handling acetylene at elevated temperatures and/or pressures, inorder to eliminate the explosive hazards characteristic of acetyleneunder .such conditions.

actions involving the use of acetylene under'elevated temperatures orpressures.

From the standpoints of economics and prospective availability,acetylene remains one of the most attractive raw .materials in theentire organic chemical field. Although many valuable reactionsinvolving acetylene are known, the

commercial exploitation thereof has been greatly retarded by the fearzofviolent explosions. As is relates to the .handling of acetylene and isparticularly concerned with In its more specific embodiments, thepresent invention is particularly concerned with improvements inrewellknown to. those. experienced in this art,

acetylene, under elevated pressuresand particularly at elevatedtemperatures, is inherentlyunstable; In general, apressureof about -15pounds per square inch is consideredthe maximum pressure at whichacetylene maybe handled with rel-' ative safety and, at, allhigherpressures orat elevated temperatures or Sunder a combination ofboth conditions.,great care has to be, exercised and expensive andcomplicated mechanical instablations have to be .provided in order Itominimize theldanger oi explosion. However, even withthe most elaboratesafety A precautions, explosions may occursjimply, because acetylene,under, elevated pressures and temperatures, is inherently I'heinstability -,of acetylene. at elevated preslsuijesan'd; temperatureshas seriously limited its "use and complicated its handling andjuse;Thus,

lion onoxideio'r; mixturesffthere'of. 1 However, the

of diluent g a"s"re quired "to; render the mixture non-explosiveunder"normal perating con it ons; sfhighffgenerally 50% or h ighfer, so"that the investment due to 'thellarger sized com- 12 Claims. (ctzen-e14) merely handling the acetylene with safety. The effects of'theuse ofinert' gases in order to produce a diluted acetylene which isnon-explosive, are even more pronounced in many chemical process stepsto which the acetylene is subjected. Thus, the use of a diluent gassubstantially increases the over-all pressure which must be employed inprocessing steps, thus further increasing the capital cost. At the sametime, the presence of a diluent frequently results in a'lowered rate ofreaction and has'other undersirable process effects.Thefe'xplosivelimits of acetylene-nitrogen mixtures, for-example, whichhave been employed most commonly heretofore, demand that, above C. and100 pounds per square inch pressure,

where the vast majority of. acetylene reactions must be run to proceedat a -practical rate, the acetylene be diluted with at least 55%nitrogen to remain within the non-explosive range. It is obvious thatwhen one adds together the partial pressure due to theinert gas, thepartial pressure due to the starting materials and the partial pressuredue to thereaction products, the grand total makes the partialpressur'eexhibited by acetylene appear low. The relatively low concentration ofacetylene in such mixtures therefore adversely affects the reaction rateand diminishes it to such an extent that many processes involving theuse of acetylene have been rendered economically unsound.-- It'is,therefore, obvious that nitrogen and other diluent gases can be employedto introduce a safety feature into a process involving the useotacetylene at an elevated pressure or temperature only-at the expense ofa. high over-all operating pressureand a relatively low partial pressureof acetylene with a consequent lowering of the reaction rate.

Briefly stated, the present invention comprises a process for renderingacetylene non-explosive in order that it may be safely handled oremployed inv chemical-reactions by saturating. the acetylene ,,with,thevapors of a normally liquid, suitablediluent. We have discovered thatwhen acetylene-,lsdiluted with'a normally liquid diluent having a-relatively. high vaporpressure, substantially. smaller amounts of suchdiluent may be employed to produce a non-explosive mixture, ascompared-with inert diluent gases. The saturated acetylene may be safelyhandled and particularly outstanding advantages are obtained in processsteps to which the saturated acetylene is employed. x Thus, we havefound that the-overis substantially increased. Additional advantages 3are provided by savings in the size of necessary compressors andcompressing work, particularly in processes requiring recirculating ofthe gas.

We term our process of saturating acetylene with a normally liquiddiluent having a relatively high vapor pressure as a carburizing" or"carbureting" process and the non-explosive mixtures, more fullydescribed hereinafter, of acetylene and such normally liquid diluentshaving relatively high vapor pressures will hereinafter be referred toas "carburized or carbureted" acetylene. As employed in the presentspecification, the terms carburize, "carburete and the like are used inthe broad sense of enriching a gas with the vapors of a volatilenormally liquid compound, and are not used in the restricted sense ofenriching a gas by the addition thereto of an agent of a higher carbonto hydrogen ratio than the lean gas itself. Such a restricted meaningfor the term is obviously inapplicable in the present instance, since,in general, the diluents available for use in the present invention havea lower carbon to hydrogen ratio than acetylene.

The diluent which is employed to carburize the acetylene may be an inertdfluent or frequently may advantageously be a compound with which theacetylene is to be reacted or a product of the reaction. Thus, in theevent the acetylene is to be employed in a chemical reaction in whichone of the reactants is anormally liquid compound having a relativelyhigh vapor pressure. as is frequently the case, such reactant mayadvantageously be employed as' the diluent for the acetylene in themanner more duly hereinafter described. Again, in many cases, someproduct of the reaction may be a normally liquid compound which issuitable for use as a diluent and may be so used advantageously.However, if desired, many of the advantages of the present invention maybe obtained. even in such cases, by employing an inert diluent and, ininstances where the compounds to be reacted with acetylene, or theproducts of the reaction, have too low a vapor pressure to besatisfactory for use as .diluents, a normally liquid organic compound,

which is inert under the conditions of the reaction, may be used as adiluent.

The particular compound which may most advantageously be employed as thediluent will depend, especially if the acetylene is to be employed in a.chemical reaction, on the particular reaction in which it is to beemployed and also on the conditions, especially the temperature andpressure, under which the acetylene is to be handled or used. Suitablecompounds for use as inert diluents under a relatively wide range ofconditions are the lower boiling liquid hydrocarbons, ethers or esters,for example, aliphatic or cycloaliphatic hydrocarbons, such as, hexane,heptane, octane, cyclohexane or others, and isomers or mixtures thereof;also may aromatic or naphthenic hydrocarbons, such as benzene ortoluene, may be employed. In addition, certain heterocyclic compounds,such as furfural, pyridine and the like, are suitable for use. Among theesters and ethers suitable for use as diluents are numerous productsobtainable from'reacting acetylene with alcohols or acids, such asn-butyl vinyl ether, vinyl acetate and others, in addition to suchsaturated ethers and esters as di-ethyl ether, ethyl acetate and thelike. It should be understood that a compound which may serve as aninert diluent under the conditions of one process may be a reactant inor cause an undesirable secondary reaction under the conditions ofanother process. Those skilled in the art can readily select suitablediluents, either an inert diluent, a reactant or a product of thereaction, for use in any specific process.

In order to simplify the description of the present invention, it willfirst be described, with particular reference to its use, in reactionsinvolving the use of acetylene. In order to facilitate the presentdescription, there is appended hereto several sheets of drawings inwhich the several figures are diagrammatic representations of apparatussuitable for use in practicing the process of the present invention.

In the drawings:

-Fig. l is a schematic representation of one form of apparatus suitablefor use in practicing this invention.

Fig. 2 is a flow chart illustrating another form of apparatus suitablefor use in practicing this invention.

Figs..3 to 8, inclusive, are schematic illustrations of several specificforms of "carbureting devices suitable for use in practicing thisinvention, while Figs. 9 and 10 are schematic illustrations of two typesof compressors which also are adapted to function as "carburetingdevices for use in practicing this invention.

When it is desired to employ the batch process for acetylene reactions,as is generally the case when the product formed has too high a boilingpoint to be distilled continuously from the reaction vessel under theconditions of temperature and pressure at which the reaction is carriedout. a. type of apparatus illustrated in Fig. 1 may be employed to goodadvantage. As there illustrated, acetylene at a low pressure,atmospheric or at most a few pounds superatmospheric pressure, is ledfrom a suitable source, illustrated in the drawings as gas holder I,through line 2 to carburetor 3, wherein it is saturated with a suitablediluent, the carburetor 3 being maintained at such a temperature as tocause the desired F degree of saturation of the acetylene stream withthe diluent vapor. The saturated acetylene is then passed through line 4to compressor 5, illustrated as a. heated liquid seal centrifugalcompressor, where it is brought to the desired pressure, and thencethrough line 6 and preheater 1, if a further increase in temperature tothe reaction temperature is necessary, and thence is introduced into thepressure autoclave 8 which is maintained at the correct temperature andpressure for the particular reaction in question to take place.

By this method, the dfluent in the carburetor 3 is gradually transferredto the autoclave 8. If the diluent has a vapor pressure greater than thepressure at which the reaction is being run, it may be continuouslyreleased through line 9 by means of release valve I, along with anyunreacted acetylene, into condenser I I, wherein the diluent iscondensed and thence flows to surge storage tank I2, the acetylene beingwithdrawn through line i3 and returned to line 2. The recovered diluentis removed from surge tank l2 by make-up pump it and returned tocarburetor 3 through line IS. A portion of the diluent may be suppliedthrough line ii to heated compressor 5 to serve as a liquid seal andcarbureting agent, as will be more fully described hereinafter.

As stated above, the batch process is most advantageously applicable toacetylene reactions in which a relatively high boiling product, i. e.,

one which is notvaporized'at the temperature and pressure existing inthe reactor, is produced. Consequently, in such process, the diluentemployed is either a reactant or an inert diluent. However, it will beapparent to those skilledin the art that a process may be applied toacetylene reactions in which a relatively low boiling product isproduced. In the event that the product is lower boiling than thecompound reacted with acetylene, a portion oi the product present as avapor in the autoclave 8 maybe removed, along with acetylene, throughdraw-oil line 8, being'condensed in condenser II and separated from theacetylene in surge tank l2 and returned to carburetor 3 through line I3vby pump Ii, and thus serve as a diluent for the acetylene. In the eventthat a reactant is employed as a diluent, all .or a portion of thereactant may be introduced into the process as a diluent through line I!to pumrril and thence through line I8 to carburetor 3." Various othermodifications will be apparent to those skilled in the art and certainsuch modifications are more particularly described hereinafter and inthe specific examples.

In Fig. 2, there is illustrated diagrammatically,

actants may be introduced into make-up tank 38 through line 48 and areagain introduced into an apparatus suitable for acetylene reactions 7which may be conducted in a continuous manner.

As illustrated in the drawings, acetylene from a low pressure source,such as acetylene holder II,

is introduced into theprocessthrough line, being passed, ifdesired,through scrubber 23 and dryer 24 to bufier tank 25. From low pressurebuffer tank 25, the acetylene is withdrawn through line 26 to carburetor21, wherein-it is saturated to the desired degree with the vapor of asuitable liquid diluent, the temperature oi the carburetor being soadjusted as to give the desired degree of saturation oi the acetylene,at

the pressure used, with the particular diluent being employed. Thesaturated acetylene flows then through line 28 to compressor 28, whereit is raised to the desired pressure, and is then introduced intoreactor 32 through line 38, first passing through preheater 3i, iffurther heating is required in order to maintain the desired reactiontemperature. Other reactants may be introduced into reactor 32 throughline 33. The reactor 32 may be of any desired design and the reactionproducts are continuously removed therefrom through line 34 and may bepassed to I any necessary separating means.

As illustrated in the drawings, only such of the .reaction products asare vapors under the conditions maintained in reactor 32 are removedthrough line 34 and, after passing pressure release vvalve 35 therein,flow through condenser 33 todegasser 31. Any unreacted acetylene iswithdrawn from separator 31 to line 38 andreturned therethrough tobufler tank 25 for recirculation. The

tank 43. The unreacted starting material is returned from still bottom48 through line 44' to make-up tank 45. Anynecessary additionalrereactor 32 through line 33 by make-up pump ll, a portion of thereactant also being returned through line 48 to surge tank 48. Diluentis withdrawn as needed from tank 43 by pump 58 and introduced throughline II to carburetor 21, a portion 01' the diluent being introducedthrough line 52 to compressor 28, it needed, to serve as a liquid sealand carbureting agent therein.

It will be apparent that the specific method employed for separation ofthe reaction products withdrawn from degasser 3'1 iorms, per se, no partof the present invention andthe particular details thereof may readilybe determined by those skilled in the art for eifecting the desiredseparation. In particular, it will be noted that slight modifications ofthe method of and appar'atus' for separating the reaction products maybe necessitated by the state in which the reaction products areobtained. Thus, depending on the relative boiling points of the variouscomponents thereof, the specific method of separating the reactionproducts may have to be modified somewhat from that Just described.

It should be understood that in place of a simple carburetor of the typediagrammatically illustrated in the accompanying flow charts, Figs.

1 and 2, any suitable type of carburetor may be employed. Thus,-a seriesof simple carburetors, as illustrated in Fig. 3, may beemployed. As

thereillustrated, the acetylene gas flowing through line 8i is bubbledthrough a pool of dilu-- ent in receiver 82 and is partially saturatedtherewith. It then flows through line 83, through a, second pool ofdiluent in receiver 84 which may be maintainedat. a higher temperature.by suitseries may be employed.

.In Fig. 4, there is illustrated an'aspirator-type '0I carburetor inwhich acetylene, passing Venturi principle.

through line H, is carbureted by a diluent from \container 12, throughPitot tube '13. In Fig. 5,

there is illustrated a carburetor based on the Acetylene enters' throughPipe 8i into chamber 82, where it is mixed with vapors oi carburizingagent coming from heated container 83 through tube 84. The carburetedgas leaves through exit pipe 85. In Fig. 6, there ,is illustrated amechanical type carburetor in which acetylene enters the mixingchamber82 through pipe St. The liquid carburizing agent is introducedinto the chamber through pipe 93 onto a mechanically driven distributorplate 84. The carbureted gas leaves the chamber through exit pipe 95. InFig. 7, there is illustrated a baille type carburetor in which acetyleneenters the mixing chamber I03 through pipe IIII. The vapors of thecarburizing agent are led into the mixing chamber through pipe I 02, andthe carb'ureted acetylene leaves through exit pipe I34. In largecommercial installations, the carburization of acetylene may beperformed with advantage in towers, as illustrated in Fig. 8. Acetylenefrom storage tank H3 is drawn through line I to carbureting tower II5,where it passes upward over filler bodiesand out through exit pipe I I8to compressor Ill, where it is raised to the desired pressure and thecompressed carbureted gas is removed through line H8. The carburet .ingagent is circulated over the filler bodies by means of lines sand I20 bypump HI and is heated to the desired temperature in heater I22.Carbureting medium is withdrawn from storage tank I23 by pump I24, asneeded, and introduced through line I25 to the suction side of pump I2I,

a portion of the carbureting agent being sent through line I26 tocompressor III to serve as a liquid seal and carbureting agent therein.

In order to avoid any explosion hazards during I the compression of theacetylene gas from atmospheric or lower pressure to the pressure atwhich the reaction takes place, it is advisable to add of the solventsaturated gas is increased sufliciently before compression so that nocondensation of the vapors can occur in the compressor. An additionalsafety feature may be provided in 8 rated from the acetylene, asillustrated in the drawings. Likewise, in the type of apparatusillustrated in Fig. 2, any vapor space in the reactor 32 should befilled with a diluted mixture of unreacted acetylene, if any, anddiluent, and only after the pressure on the acetylene has been reducedon passing pressure release valve 35 should the acetylene be separatedfrom the diluent, as illustrated in the drawings. The necessity of thisprecaution should be borne in mind in selecting a diluent for use in anyparticular process, in order that in any vapor space in the apparatus inwhich acetylene, under pressure,

may collect, it will be diluted and thus rendered non-explosive. It willbe apparent that at times, one diluent, for instance a reactant, may beemployed as a diluent for acetylene prior to its enthis case bymaintaining the temperature of the compressor above the dew point of thediluent vapor at the given pressure. acetylene may also be compressed byusing blowers, liquid piston pumps or other suitable apparatus whichpermit the compression of moist gases.

It is also possible, by employing a blower-type compressor with a liquidseal (Nash Hytor type), to cause the sealing medium to act as thecarburizing agent, by the simple means of keeping the blower at asuitable temperature to ensure proper saturation of the acetylenepassing therethrough.

Equipment which is satisfactory for the simultaneous carburization andcompression of acetylene is schematically shown in Figures 9 and 10. InFig. 9, there is illustrated a carbureting centrifugal compressor, theacetylene entering through line I32 into the heated compressor I33,where it is carburized and compressed, and leaves through exit pipe I34.The carburizing agent, which acts as a liquid seal in the compressor, isreplenished from storage tank I35 through lines I36 by means of make-uppump In the carbureting piston compressor, illustrated in Fig. 10,acetylene enters through inlet pipe I over suction valve I42 into thecompression chamber I43, filled with the liquid carburizing agent. Theliquid in chamber I43 is moved by mechanical piston I44 and acts as aliquid piston. Suitable means, such as jacket I45, are provided forheating the carburized liquid in order to effect the desired degree ofsaturation of acetylene. The compressed carburized acetylene leaves thechamber I45 over discharge valve I46 and exit pipe I41. The oarburizingagent is re- 'plenished from storage 'tank I48 through lines I49 bymake-up pump I50.

It should be noted that in practicing the process of the presentinvention, it is desirable that the acetylene be diluted, at all times,while it is under pressure or at an elevated temperature. Thus,referring back to Fig. 1, it will be noted that if all the acetylenedoes not react in autoclave 8 and a portion thereof is withdrawn forrecirculation through line 9, the diluent employed should be such that,in the vapor space in autoclave 8, a sufficient amount of diluent willbe vaporized to dilute the acetylene collecting therein and withdrawnthrough line 9. After the acetylene passes pressure release valve I0 andthe pressure is reduced sufficiently to remove the danger of explosion,the diluent may be sepa- The carbureted tering the reaction zone, andanother diluent, for instance a reaction product, may function as adiluent for the acetylene, while it is still under pressure and after itleaves the reaction zone.

The degree to which the acetylene should be diluted with a diluent ofthe type specified will of necessity vary with the pressure at which theacetylene is to be used and, at a given pressure, the extent of dilutionwhich is necessary varies with the particular diluent being employed.For example, with methanol vapor as a diluent, the explosion limits areshown in the following data:

Per Cent Lbs./sq. in.

Abs. Acetylene Those skilled in the art can readily determineexperimentally the degree of dilution which is required at anyparticular pressure and with any specific diluent. Likewise, thetemperature at which the carburetor should be held in order to securethe desired degree of dilution can readily be determined by simpleexperimentation by those skilled in the art. For example, the limits ofexplosibility may easily be determined by enclosing acetylene gastogether with a predetermined amount of diluent vapor in a pressurevessel, heating the vessel up to the test temperature, and initiating apossible explosion by means of an electrically heated wire, providedinside the pressure vessel.

In order tomore fully illustrate the practice of the present invention,examples of its use are iven in several difierent fields. It should beunderstood that these examples are merely for the purpose ofillustration and that the invention is not limited thereto. It will beunderstood that the pressures referred to in these specific examples andelsewhere in this specification are gauge pressures (superatmospheric),unless they are otherwise specifically defined.

Example 1 The process of the present invention may advantageously beemployed for the production of vinyl ethers, for instance, by theprocess described in United States Patent No. 1,959,927 to Reppe, inaccordance with which acetylene is caused to (I II Operating Conditionsgm? g gfi System Pressure pounds per square inch 250 45 Temp. ofVlnylation .C 150 145 Acetylene Conoentration}1n Gas to Re- 67 99Nitrogen Concentration actornper cent 33 Catalyst Concentration. do 2525 Time of Run ..liours 8 8 Yield Ethyl Vinyl Ether pounds- 168 272Yield Ber hour .-pounds per hour- 21. 0 34 Yield ased on Ethanol percent.- 88 97 Example 3 In the production of n-butyl vinyl ether inaccordance with the principles of the present invention, an apparatus ofthe type illustrated in Fig. 2 may be employed. The vinylation tower 32is charged approximately full with n-butanol in which is dissolvedslightly less than A part of potassium butylate. the ratio by weight ofbutanol to potassium butylate being 240:623. The entire system is keptanhydrous and oxygenfree. Acetylene from holder 2! is passed throughwater-scrubber 23, dryer 24 and butter tank 2!, held at a pressure of 4pounds per square inch, and introduced into carburetor 21, containingliquid n-butanol at a temperature of 102 C. The acetylene becomessaturated with n-butanol and is then compressed by compressor 29 to 45pounds per square inch, and thence passes into preheater 31, held at 145C., and thence finally into the bottom of vinylation tower 32.

The vinylation tower is held at a temperature of 150 C. and under apressure of 45 pounds per square inch. n-Butanol is suppliedcontinuously to the bottom of the tower through line 33 by means ofpressure pump 41 from make-up tank 45. In the reaction column 32, theacetylene reacts with the n -butanol to form n-butyl vinyl ether inaccordance with the following equation:

There is continuously withdrawn from reactor 32 through line 34 amixture of n-butyl alcohol, n-butyl vinyl ether and unreacted acetylene,the pressure thereon being reduced on passing pressure release valve 35to approximately 4 pounds I per square inch. The separation and.recovery of the n-butyl vinyl ether and recirculation of acetylene andbutanol is the same as that described under Examples 1 and 2 for methylvinyl ether and ethyl vinyl ether respectively. The vinyl n-butyl etheris obtained in 96-98% yields as a clear colorless liquid, boiling at93-94" C.

Under substantially the same conditions of operation as those mentionedabove, the vinyl ethersof other lower aliphatic alcohols, such asn-propyl, isopropyl, isoand secondary butyl alcohol may readily beproduced.

Example 4 The specific process described above in which there iscontinuously removed from the reactor a mixture of reactants and productin vapor phase, cannot readily 'be applied to the production of vinylethers of alcohols containing more than 4 carbon atoms, due to the factthat the vapor pressures of the resulting vinyl ethers are too low todistill out of the reaction tower under the operating, conditions.However, the process of the present invention may readily be applied tothe production of the vinyl ethers of higher alcohols by slightmodification of the process and may advantageously be carried out inapparatus of the type illustrated in Fig. 1. Thus, octadecyl vinyl ethermay readily be prepared from acetylene and octadecyl alcohol.

The autoclave 8 is charged with 340 parts of octadeca-nol, 14 parts ofpotassium hydroxide and 40 parts of cyclohexane. The entire system ispurged free'of oxygen by nitrogen and the nitrogen is then removed byevacuation. The temperature of the autoclave is brought to 160 C., themajor portion of the cyclohexane being vaporized and transferred duringthis time via line 9, release valve i0, condenser ll, surge tank I2 andpump I4 to carburetor 3. The carburetor 3 is filledwith cyclohexane andbrought to 79 C. Acetylenefrom holder I, at a pressure of 4 pounds persquare inch, is passed through the carburetor 3, where it becomessaturated with cyclohexane and the saturated gas is passed into thecompressor 5, where it is brought to a pressure of 45 pounds per squareinch. Thence it is passed through preheater I, maintained at 0., andfinally enters the autoclave where it reacts with the octadecanol toform octadecyl vinyl ether in accordance with the following equation:

A total of 33 parts of acetylene is absorbed over a period of 2 hours.During the reaction, the cyclohexane in the carburetor is graduallytransferred into the autoclave and is continuously withdrawn therefrom,along with unreacted acetylene,

through line 9 and on passing pressure release valve I 0, the pressurethereon is reduced to 4 pounds per square inch. The cyclohexane iscondensed in condenser ii and the condensate separated from acetylene insurge tank l2, the acetylene being returned through line 13 to the line2, while cyclohexane is removed from surge tank i2 by pump i4 andreturned to carburetor 3. The condensing of the cyclohexane, and thereturning of the condensate into the carburetor by means oi. pump it maybe avoided by mixing the saturated cycle gas, after pressure releasewith make-up acetylene in a suitable buffer tank, and feeding themixture into the carburetor and compressor. On completion of thereaction in the autoclave to the desired extent, the reaction mixturetherefrom may be distilled under vacuum and vinyl octadecyl ether,boiling at 190 C. at 10 mm., is obtained in a yield of 98%.

In a similar process using nitrogen as a diluent for the acetylene in aratio of 1:1 by volume, a pressure of -225 pounds per square inch and atemperature of 150 C. is required to obtain a satisfactory rate ofreaction.

In addition to the production of the specific vinyl ethers described inthe foregoing examples, 1-4 inclusive, it will be understood that theprocess of the present invention is broadly applicable to the field ofpreparation of vinyl ethers 13 and those skilled in the art can readilyadapt the principles of this invention to the production of any specificvinyl ether. Thus, the process of the present invention may beconsidered to be broadly applicable to the reaction of acetylene withhydroxy compounds corresponding to the formula:

on R/ x in which X represents --H, -COOH, COO metal, -NY:, -(OR)OH or(OR)-OR groups, It being an aliphatic, hydroaromatic, or aromatic,preferably hydrocarbon radical, or an aralkyl radical, Y being -H,---Ror ROH and n being naught or any integral number.

The organic. hydroxy compounds may be chosen from monoand polyhydricaliphatic and cyclic alcohols, from phenols, naphthols,hydroxy-carboxylic acids, or metals thereof, respectively, and partiallyetherified polyhydrlc alcohols, partially esterified polyhydric alcoholsreacting-like mixtures of alcohols and acids owin to a saponlfication bythe alkali present Specific compounds of these types are, for example,alcohols, such as methanol, ethanol, nand isopropanol, butanols,hexanols, octanol, decanol, d'odecanol, tetraand octadecanols, docosanoland montanol; glycols such as ethylene-(propylene, 1.'3-butylene-,diethylene-, triethylene-, and tetraethylene glycols; 'polyhydroxycompounds such as glycerol, pentaerythritol and their alliyl and arylethers: hydroxy carboxylic acids," or their salts, respectively,-such"as"alkali metal glycolates; amino alcohols, as for example'mono-,di or tri-alkylolamineagsuch as mono1;-,,ui-,or trhethanol or" propanolamines or; mono -alkyl mono or 'di-ethanol amines such N-jniethyL,

or 'N-cyclohexyl, -N-di-ethanol amines; and bydroxy compounds containingaromatic .inuclei,

such as phenol, and alkylrsubstituted phenols,

cresoLbenzyl alcohol and aand p-naphthols. As specific phenols maybementioned para-tel.- tiary-butyl phenol, or para-isooctyl phenol. IAnother process to which the present invention may convenientlybeapplied is the production of N-vinyl compounds by the reaction of-acetylene with compounds containing the pyrrole Example 5 For theproduction of N-vinyl carbazole from acetylene and carbaz'ole, the typeof apparatus shown in Fig. 1 may be used conveniently. The autoclave 8may be charged with a solution or suspension of carbazole in a suitablesolvent, for instance a cyclohexane solution oi. carbazole in which theratio of cyclohexane to carbazole is approximately 2:1 by weight. Thenecessary 14 catalyst may also be incorporated in the solution chargedto the autoclave and the entire system purged free of oxygen by means ofnitrogen and the nitrogen then removed by evacuation.

The carburetor 3 is filled with cyclohexane and brought to a temperatureof 79 C. and the autoclave is brought to 165 C. Acetylene from holder l,at a pressure of 4 pounds per square inch, is passed through thecarburetor 3, where it becomes saturated with cyclohexane, and then iscompressed to a pressure of 170 pounds per square inch. Thence it passesthrough preheater l, maintained at 145 C.,and finally into. theautoclave 8, where it reacts with the carbazole present therein to formvinyl carbazole in accordance with the following equation:

nczcn+ I During the reaction, unreacted acetylene is drawn off throughline 9, together with vaporized cyclohexane, and on passing pressurerelease valve l0, set at 1'70 pounds per square inch, the pressure isreduced to 4 pounds per square inch. The cyclohexane is condensedin'condens'e'r ii and the condensate separated from the acetylene insurge tank 12. The acetylene is'returned through line l3 to line 2,while the cycloh'exane is returned by pump Mto carburetor 3 when the"theoretical amount'of 'acetyl'eneliasbeen employed (in approximately 2hours)f,'the1 eao ti onrnixtujre is a glloviied to cool. Kftencobling,the reactionmixture may be filtered "to remove insoluble catalysts andthe filtrate 'sublbt 'to' iractidnalf distillation. has removal of'{thecycloh'exa'nejby1 distillation, t e vinyl'carbaizole maybe'fdistilled' under vacuum. The yield obtained is-9-99%of thetheoreticalfyield'." In comparison with theabove processin whichthejdiluent employed for the reaction is employed to'carburize theacetylene, when, a /40 acetylene-nitrogen mixture is employed in anotherwise identical process, the reaction requires somewhat higherpressures, a longer time, ,approximately 14 hours, and the yield islower, amounting to only Example 6 55 Another N-vinyl compound which mayreadily be produced in accordance with the present invention is N-vinylphenyl alpha-naphthylamine, an apparatus of the type illustrated in Fig.1 being suitable for this purpose.

5 The autoclave 8 is charged with 30 parts of phenylalpha-naphthylamine, 30 parts of Pyridine and 1 part of potassiumhydroxide. The entire system is purged free of oxygen by means ofnitrogen and the nitrogen is then recovered 5 by evacuation. Thecarburetor 3 was filled with pyridine and brought to a, temperature of114 C., and the autoclave was brought to 160 C. Acetylene from theholder I, at a pressure of 4 pounds per square inch, is passed throughthe 70 carburetor 3, where it becomes saturated with pyridine at C., and'is compressed to 120.

pounds per square inch. It is then passed through preheater I,maintained at C., and finally to the autoclave 8 where it reacts with 75phenyl alpha-naphthylamine to form N-vinyl phenyl alpha-naphthylaminethe following equation:

in accordance with HCECH -iduced pressure. N-vinyl phenyla-naphthylamine' is'obtained in 90-95% yild; boiling point 168- 170 C.under 1 mm. pressure.

In comparison with the above process, in a similar process for producingN-vinyl phenyl alpha-naphthylamine described in United States Patent No.2,087,079 in which a mixture of acetylene and nitrogen in, proportionsof 2:1 is employed in place or acetylene carburized with pyridine,temperatures of 180-190 C.,and pressures of 225-375 pounds per squareinch are required.

Another broad field to which the process of the present invention isbroadly applicable is the production of vinyl esters by the action ofacetylene on carboxylic acids of all types, i. e., the vinyl esters ofaliphatic, saturated and unsaturated, monoand poly-carboxylic acids; ofcyclic, that is aromatic, cycloaliphatic and heterocyciic, monoandpolycarboxylic acids and of mixed aliphatic-aromatic and mixedaliphatic, cycloaliphatic, monoand polycarboxylic acids, the carboxylicgroups of which mixed acids may be fixed to the aliphatic as well as thecyclic residue.

Suitable mono-aliphatic carboxylic acids are, for example, formic acid,acetic acid, propionic acid, lauric acid, palmitic acid, margaric acid,stearic acid, and oleic acid; suitable dicarboxylic acids are. forinstance, succinic acid, adipic acid, myristic acid and sebacic acid;suitable cyclic acids are, for example, aromatic carboxylic acids suchas benzoic acid, o-,-m-, and p-toluic acids or abietic acids, and thedifferent isomers of naphthoic acid, cinnamic acid, phenylglycine, andpolybasic cyclic acids or their acid esters. such as, phthalic acid andphthalic acid mono alkyl esters, for example, monoethyl, nor isobutylesters, cyclic hydroxy-carboxylic acids, as for example, salicyclic acidor hydroxy-naphthoic acid, and heterocyclic acids, such as pyridine andquinoline carboxylic acids, and hydroaromatic carboxylic acids, as forexample, hydrophthalic acid. Instead of pure acids, partially esterifiedacids or resins showing a high acid value, such as colophony, ormixtures of acids may be employed, as for example, the mixtures of acidsobtainable by the saponification of natural fats and fatty oilscontaining esters or fatty acids, or the asvaoas 16 mixtures of acidsobtainable by oxidizing parafiin wax or Montan wax. The specific use ofthe present invention in the production of vinyl esters is illustratedby the following specific examples, 7-9, inclusive, and from. aconsideration thereof, those skilled in the art can readily determinethe specific details of applying the present invention to the productionof other vinyl esters.

Example 7 A process for producing vinyl esters is described in UnitedStates Patent No. 2,066,075 to Reppe, in accordance with which vinylesters are prepared, working in liquid phase, by the action of acetyleneon carboxylic acids using zinc or cadmium salts of carboxylic acids ascatalysts, using preferred temperatures of -190 C. and preferredpressures of 10-20 atmospheres and in which the acetylene is dilutedwith inert gases, such as nitrogen, hydrogen, or carbon monoxide in'order to preclude explosions, may readily be practiced in accordancewith the present invention by carburizing the acetylene in place ofusing an inert diluent gas. When so modified, it can be run at greatlyreduced pressures, free from danger of explosion.

Thus, vinyl acetate may readily be produced in accordance with thepresent invention in an apparatus of the type shown in Fig. 2. Thevinylation tower 32 is charged with glacial acetic acid, in which isdissolved approximately 4% by weight of zinc acetate. The entire systemis kept anhydrous as well as oxygen-free to prevent the formationofundesirable 'by-products. The tower I2 is held at a temperature of C.and under a pressure of 45 pounds per square inch.

Acetylene from holder 2| is passed through water-scrubber 23 and dryer24 in order to remove water-soluble impurities, particularly acetone,and the last traces of moisture, and thence flows to buffer tank 26where it is held at a pressure of 4 pounds per square inch. Theacetylene from bufler tank 25 passes into carburetor 21, containingacetic acid held at 118 C. The acetylene becomes saturated with aceticacid and then is compressed in compressor 29 to 45 pounds per squareinch and thence passes into preheater 2|, held at a temperature of 145C., and finally into vinylation tower 32. Glacial acetic acid iscontinuously supplied to the tower 32 through line 33 by pump 41 frommake-up tank 45. In the tower 32, the acetylene reacts with the aceticacid in accordance with the following equation:

The vinyl acetate, along with unreacted acetic acid and acetylene, iscontinuously withdrawn from the top of tower 32 and on passing throughpressure release valve 35, set at 45 pounds per square inch, thepressure is reduced to 4 pounds per square inch. The vinyl acetate andacetic acid are then condensed in condenser 35 and the acetyleneseparated therefrom in degasser 31 and returned through acetylene returnline 38 to butfer tank 25. The vinyl acetate and unreacted acetic acidare continuously withdrawn from degasser 31 and introduced intostripping still 40. The vinyl acetate is taken off overhead at '13-'74C. through line 4 I, condensed in condenser 82 and collected in productreceiver 43. The unreacted acetic acid is returned from the still bottom through line 44 to make-uptank 45.

On subsequent conventional fractionation of the product from receiver43, vinyl acetate is oba 7 tamed as acolorless liquid, boiling at 73 C.in 85-95% yield.

Example 8 In the production of vinyl valerate in accordance with thepresent invention, by applying the principles thereof to the processdescribed in th above-mentioned United States Patent No. 2,066,075, anapparatus of the type disclosed in Fig. 1 may be employedadvantageously.

The autoclave 8 is charged with 40 parts-byweight of valeric acid,parts-by-weight of cyclohexane and 1 part-by-weight of zinc acetate. Theentire system is purged free of oxygen by means of nitrogen and thenitrogen is then removed by evacuation. The temperature of the autoclaveis then brought to 170 C. During this period, the majority of thecyclohexane is transferred to the carburetor 3 through pressur releasevalve l0, set at 45 pounds per square inch'.

The carburetor 3 is filled with cyclohexane and brought to a temperatureof 79 C. Acetylene from holder I, at a pressure of 4 pounds per squareinch, is passed through the carburetor 3, where it becomes saturatedwith cyclohexane at 79 C. and is then compressed by compressor 5 to apressure of 45 pounds per square inch. Thence it passes through thepreheater I, held at 145 C., and finally enters the autoclave 8 where itreacts with valeric acid to produce vinyl valerate in accordance withthe following equation:

During the reaction, acetylene and cyclohexane are continuously removedfrom the autoclave through line 9 and on passing pressure release valve[0, the pressure thereon is reduced from 45 pounds per square inch to 4pounds per square inch. The cyclohexane is condensed in condenser I iand the acetylene separated therefrom in surge tank I2, the acetylenebeing returned through line I3 to line 2, while the cyclohexane isreturned through pump IE to carburetor 3.

When acetylene is no longer absorbed in the autoclave, the reactionmixture is allowed to cool and is then filtered to remove zinc valerate.The

Example 9 In a like manner, the process of the present invention may beapplied to the production of vinyl oleate by combining the teachings ofabove-mentioned United States Patent No. 2,066,075 therewith. For thisprocess, an apparatus of the type described in Fig. 1 is suitable. Theautoclave 8 is charged with 200 pounds of oleic acid, 40 poundscyclohexane and 14 pounds of zinc acetate. The system is purged withnitrogen and the nitrogen removed by evacuation. The autoclave is thenbrought to 160 C. During this time, the major part of the cyclohexanereturns to the carburetor I through pressure release valve [0, set at 45pounds per square inch. condenser I I, surge tank 12 and pump it. Thecarburetor 3 is filled with i8 cyclohexane and brought to a temperatureof 79 C. Acetylene from holder I, at a pressure of 4 pounds per squareinch, is passed through carburetor 3 whereit becomes saturated withcyclohexane, and is then compressed by compressor 5 to 45 pounds persquare inch. It flows thence through preheater I, maintained at 145 C'.,and

finally into theautoclave 8 where it reacts with the oleic acid presenttherein to form vinyl oleate in accordance with the following equation:

During this reaction, acetylene and cyclohexane are withdrawn fromreactor 8 through line 9 and on passing pressure release valve 10, thepressure thereon is reduced from 45 pounds per square inch to 4 poundsper square inch. The cyclohexane is condensed in condenser II and isseparated from the acetylene in surge tank I2, the acetylenebeingreturned over line 3 to line 2 while the cyclohexane is returned viapump M to carburetor 3.

When the theoretical amount of acetylene has been absorbed, the reactionmixture is allowed to cool. It is then filtered to remove zinc acetateand the filtrate fractionally distilled. After separating off thecyclohexane, vinyl oleate, boiling at 173-175 C. at 2 mm. pressure, isobtained in 90-95% yield.

It should be understood that the foregoing ex-' amples are illustrativeonly and that the present invention is in no way intended to be limitedto them. In particular, it should be noted that the conditions ofreaction, aside from the essential features of the present invention,caused by the carburetion of acetylene with a normally liquid diluent,may be varied through a relatively wide range. Specifically, it shouldbe noted that the catalysts noted in the specific examples are merelyillustrative of preferred catalysts and other agents, known to catalyzethe particular reaction under consideration, may be substituted forthose specifically disclosed. It should further be noted that otherprocess variables, such as pressure, temperature, time, relativeproportions of reactants, etc., may frequently be varied through a.relatively wide range. The particular extent of such variation which ispermissible is dependent on the specific process with which it isconcerned. It will be noted, however, that in general lower over-allpressures may be employed in accordance with the present invention andhigher efiective concentrations of acetylene will be employed than waspossible under prior art processes, except when-they were varied inaccordance with the present invention.

In addition to the specific acetylene reactions, illustrated by theforegoing examples, the present process of the invention is alsoapplicable'to a wide variety of other reactions involving the use ofacetylene under high temperatures and pressures. Therefore, it may beapplied to such reactions as the production of mono vinyl acetylene, theproduction of vinyl chloride, the production of acetaldehyde by themercury process, and the production of acetylene compounds of theformula RCECH. We do not, however, in the vention to the production ofvinyl esters and N- vinyl pyrrole compounds; these examples have beengiven for the purpose of illustrating the scope of our invention, andthe specific application of this invention to the production of vinylesters forms the subject matter of and is claimed in our applicationSerial No. 621,622, and the specific application of this invention tothe production of N-vinyl pyrrole compounds forms the subject matter ofand is claimed in our copending application Serial No. 621,621, bothfiled on even date herewith.

What we claim and desire to protect by Letters Patent is:

1. In a process involving the handling of acetylene wherein acetylene,from a low pressure source thereof maintained at conditions oftemperature and pressure at which acetylene is nonexplosive, iscompressed and passed through a high pressure zone maintained atconditions of temperature and pressure at which the acetylene isnormally explosive, the method of eliminating the danger of acetyleneexplosion which comprises contacting a stream of acetylene from said lowpressure source while it is still at a low temperature and pressureoutside the explosive range of acetylene with a volatile normally-liquidorganic compound which is non-explosive at the conditions maintained insaid high pressure zone,

said liquid with which the acetylene is contacted being in liquid phaseand being maintained at a predetermined temperature such that theacetylene on contact therewith becomes saturated with the vapors of saidnormally-liquid compound in such an amount as to form a mixture ofacetylene and said vapors in such predetermined ratio that such mixtureis non-explosive at said normally-explosive conditions of said highpressure zone, compressing the thus-obtained mixture of acetylene andvapors of said normally-liquid compound to the pressure maintained insaid high pressure zone and introducing the thus-compressed mixture ofacetylene and vapors into said high pressure zone while maintaining saidmixture of acetylene and-said vapors in said high pressure zone andduring the compression step specified at a temperature above that atwhich said vapors will be condensed, withdrawing a stream of acetyleneand said vapors from said high pressure zone and adjusting the pressureand temperature of the thus-withdrawn stream to conditions oftemperature and pressure at which acetylene is non-explosive andthereafter separating said acetylene from said normally-liquid compound.

2. In a process involving a chemical reaction between acetylene and anorganic compound known to be reactable therewith and wherein acetyleneis introduced into a reaction zone wherein a mixture of acetylene andsaid organic reactant are maintained and in which said reaction isefiected at predetermined reaction conditions of pressure andtemperature within the explosive range of acetylene, the method ofeliminating the danger of acetylene explosion which comprises contactingthe acetylene which is introduced into said reaction zone while it isunder non-explosive conditions of temperature and ressure with avolatile normally-liquid organic compound which is non-explosive at saidreaction conditions, said volatile normally-liquid organic compound withwhich the acetylene is contacted being in liquid phase and beingmaintained at such a predetermined temperature that the acetylenebecomes saturated with the vapors of said normally-liquid organiccompound in such an amount as to form a mixture of acetylene and suchvapors in such predetermined ratio that said mixture is non-explosive atsaid normally-explosive reaction conditions, adjusting the pressure andtemperature of the thus-formed mixture to said normally-explosivereaction conditions and introducing the thus-obtained mixture into saidreaction zone while maintaining said mixture at a temperature above thatat which said vapors will condense, effecting the desired reactionbetween said acetylene and said organic compound known to be reactabletherewith in said reaction zone, and recovering the product of saidreaction.

3. In a process involving a chemical reaction between acetylene and anorganic compound known to be reactable therewith, wherein acetylene isintroduced into a reaction zone, wherein a mixture of acetylene and saidorganic reactant are maintained and in which said reaction is effectedat predetermined reaction conditions of pressure and temperature withinthe explosive range of acetylene and unreacted acetylene removed fromsaid reaction zone and recycled, the method of eliminating the danger ofacetylene explosion which comprises contacting the acetylene which isintroduced into said reaction zone while it is under non-explosiveconditions of tempera-ture and pressure with a volatile normallyliquidorganic compound which is non-explosive at said reaction conditions,said volatile normally-liquid compound with which the acetylene iscontacted being in liquid phase and being maintained at such apredetermined temperature that the acetylene becomes saturated with thevapors of said normally-liquid organic compound in such an amount as toform a mixture of acetylene and such vapors in such predetermined ratiothat said mixture is non-explosive at said normallyexplosive reactionconditions, adjusting the pressure and temperature of the thus-formedmixture to said normally-explosive reaction conditions and introducingthe thus-obtained mixture into said reaction zone while maintaining saidmixture at a temperature above that at which said vapors will condense,effecting the desired reaction between said acetylene and said organiccompound known to be reactable therewith in said reaction zone andrecovering the product of said reaction, withdrawing from said reactionzone a stream of unreacted acetylene admixed with said vapors in saidpredetermined non-explosive proportions, reducing the pressure on thethus-withdrawn stream below the explosive range for acetylene andintroducing said withdrawn acetylene, after its pressure has beenreduced, into the acetylene being supplied to said reaction zone priorto the contacting step specified.

4. A process as defined in claim 2, wherein the volatile normally-liquidorganic compound with which the acetylene is contacted in the contactingstep specified is a volatile normally liquid organic compound which isnot explosive at the reaction conditions employed and which is inert atsaid reaction conditions.

5. A process as defined in claim 2, wherein the organic reactantspecified with which the acetylene is reacted is a volatile organicliquid, and in which said volatile organic liquid reactant is employedas the volatile normally-liquid organic compound specified with whichthe acetylene is contacted in the contacting step specified.

6. In a vinylation process wherein acetylene is reacted with an organichydroxy compound known to be reactable therewith, and in which saidreaction is effected at predetermined reaction conditions of pressureand temperature within the explosive range of acetylene, the method ofeliminating the danger of acetylene explosion which comprises contactingthe acetylene which is introduced into said reaction zone while it isunder non-explosive conditions of temperature and pressure with avolatile normally-liquid organic compound which is non-explosive at saidreaction conditions, said volatile normally-liquid organic compound withwhich the acetylene is contacted being in liquid phase and beingmaintained at such a predetermined temperature that the acetylenebecomes saturated with the vapors of said normally-liquid organiccompound in such an amount as to form a mixture of acetylene and suchvapors in such predetermined ratio that said mixture is non-explosive atsaid normallyexplosive reaction conditions, adjusting the pressure andtemperature of the thus-formed mixture to said normally-explosivereaction conditions, introducing the thus-obtained mixture into saidreaction zone while maintaining said mixture at a temperature above thatat which said vapors will condense, effecting the vinylation reactionbetween said acetylene and said organic hydroxy compound known to bereactable therewith in said reaction zone and recovering the vinylatedproduct of said reaction.

7. In a process for producing vinyl ethers, wherein acetylene is reactedwith an aliphatic alcohol and in which acetylene is introduced into areaction zone, wherein a mixture of acetylene and said aliphatic alcoholare maintained and in which said reaction is effected at predeterminedreaction conditions of pressure and temperature within the explosiverange of acetylene, the

- method of eliminating the danger of acetylene explosion whichcomprises contacting the acetylene which is introduced into saidreaction zone while it is under non-explosive conditions of temperatureand pressure with a volatile normallyliquid organic compound which isnon-explosive at said reaction conditions, said volatile normallyliquidorganic compound with which the acetylene is contacted being in liquidphase and being maintained at such a predetermined temperature that theacetylene becomes saturated with the vapors of said normally-liquidorganic compound in such an amount as to form a mixture of acetylene andsuch vapors in such predetermined ratio that said mixture isnon-explosive at said normally-explosive reaction conditions, adjustingthe pressure and temperature oi the thus-formed Number Name Date 928,867James July 20, 1909 1,822,525 Herrmann Sept. 8, 1931- 1,959,927 Reppe(2) May 22, 1934 2,017,355 Reppe Oct. 15, 1935 2,066,075 Reppe (1) Dec.29, 1936 2,066,076 Reppe Dec. 29, 1936 2,191,053 Walter Feb. 20, 1940 I2,404,700 Evans Oct. 15, 1935 FOREIGN PATENTS Number Country Date 5,343Great Britain, 1911 Mar. 4, 1912 450,684 Great Britain 'July 20, 193618,181 Great Britain, 1900 Aug. 17, 1901 mixture to saidnormally-explosive reaction conditions and introducing the thus-obtainedmixture into said reaction zone while maintaining said mixture at atemperature above that at which said vapors will condense, reacting saidacetylene and said aliphatic alcohol in said reaction zone to produce avinyl ether and recovering the thusproduced vinyl ether.

8. A process as defined in claim 7, wherein the aliphatic alcoholreacted with the acetylene is a lower aliphaticalcohol and wherein saidlower aliphatic alcohol is employed as the volatile normally-liquidorganic compound with which the acetylene is contacted in the contactingstep specified.

9. A process as defined'in claim 8, wherein the lower aliphatic alcoholspecified is methanol.

10. A process as defined in claim 8, wherein the 1 lower aliphaticalcohol specified is butanol.

11. A process as defined in claim 7, wherein the volatilenormally-liquid organic compound specified with which the acetylene iscontacted in the contacting step specified is a volatile normallyliquidorganic compound which is inert to both the acetylene and the aliphaticalcohol specified at the reaction conditions employed in the reactionzone.

12. A process as defined in claim 11, wherein the aliphatic alcoholspecified with which the acetylene is reacted is octadecyl alcohol.

HANS BELLER. ROBERT E. CHRIST. FRITZ WUERTH.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS OTHER REFERENCES

